I don't listen to rap (crap) music and I've never even heard of either of these two, so I don't think they're universally known.
Only tools refer to rap as crap. Why would you dismiss an entire genre of music?
It's just shouting words into a microphone and it requires no talent. Anyone could practice and become a rapper in a day, I'm just not impressed by that genre.
That's an absolute moronic thing to say, but is to be expected from the type of people who make such ignorant and clichéd statements as you do. I can guarantee if you spent a year practising you wouldn't be able to come up with even a half decent rap performance. Do poets not have talent to you? Do music producers not have talent? Do guitarists not have talent? I find it's usually the people like you that lack any sort of talent and intelligence.